Self-lubricating gear



J. R. MCCLAIN.

SELF LUBRICATING GEAR.l

APPLICATION FILED 1uLY1o,19|8.

Patented Deo. 27, 1921.

INVENTOR WITNESSES [Ila/n.

ATT'ORNEY air 'as aaa etat Joan a. meenam, or. Enenwoon, PENNSYLVANIA, assronoa 'ro wasrmenousn mac'rarc AND manuracruamo ooMrANY, A. consonancia or rnnnsmwamn,

SELF-LUBRICATING GEM,

To all whom t may concern.'

Be it known that I, JOHN R. MCCLAIN, a citizen of the United States, and a resident of Edgewood, in the county of Allegheny and State of Pennsylvania, have invented a new `and useful Improvement in Self- Iiubricating Gears, of which the following1 is a specification.

My invention relates to self-lubricating gears, and it has for its primary object the construction of a self-sustaining gear composed of impregnated sheet material and having a lubricant distributed uniformly throughout its structure.

Self-sustaining gears have been constructed of impregnated sheet material which have lubricating qualities of limited extent which I have found may be advantageously supplemented byl distributing a lubricant, such as graphite, throughout the structure. A small percentage of lubricant distributed throughout the structure of a gear formed of impregnated sheet material greatly llengthens the life of the gear if it is run dry. In view of this, one object of my invention is to construct a gear of impregnated sheet material having a lubricant uniformly distributed throughout its structure.

Another object of my invention is to construct a gear or machine element o f impregnated 'sheet material, the gear or machine element being cut from preformed blanks and containing a wax which will insure a finished product having a smooth surface.

It is well known that certain materials, such, for example, as aphite, possess desirable lubricating qualities but. are non-adhesive and, if distributed in a structure comprising sheet material impregnated with a suitable binder, will tend to reduce the strength of the final product. In View of this, a still further object of my invention is to so construct a molded article of'im'- pregnated fibrous material containing unlformly distributed graphite that there shall be no undue weakening of any part 'of the structure. 0

With these and other objects in view, my invention will be more fully understood by reference to 'the drawings in which Figure 1 is a side elevation of an ordinary spurgear constructed in accordance with my 1n- .vention, and Fig. 2 is a diametral sectional view of the gear shown in Fig. 1.

Specification of Letters Patent.

Patente@ nee, at, tesi..

Application lfed July 10, 1918. Serial No. 244,157.

In practising my invention, I employ Athen heated to slightly dry the phenolic condensation product. The material thus treated may then be coated on one side with a mixture of an adhesive, such as a phenolic condensation product and graphite, great care being taken to insure a uniform distributlon of the graphite over the treated sheet material. A preferred treatment of the duck is to subject it to a bath of adhesive material containing graphite after which it may be sllghtly dried and an additional coatlng of adhesive, without graphite, may be applied, thus insuring undiminished blndlng action between the layers of material. The material thus treated ma then be cut in suitable sheets and stac ed to a predetermined thickness. The stacked sheets may then be subjected to heat andV pressure to compact the material andharden the binder, after which a furthery application of heat may be employed to thoroughly dry the structure and convert it toa hard, insoluble mass. The plates thus formed may then be machined in the-usual manner em-v ployed in constructing ears.

It has been found a vantageous to' add a small percentage of wax in the mixture containingthe graphite for the reason that, when the teeth are cut in the Epreformed plates, .a smoother surface may be obtained.

In Fig. 1 is shown an ord-inary spur-gear 'having a body portion 1 andl teeth 2, the

body portion 1 and teeth 2 both being of the same material, which may be duck impregnated with a binder, such as-a. phenolic condensation product. Duck is preferred on account of its resilient qualities and the close graphite to reduce the binding effect of theI adhesive. If duck is employed as the sheet material forming the body portion 1 and the teeth 2, it is found advantageous to employ a small percentage of wax distributed throughout'the entire structure so that, when the teeth 2 are cut, the Working surfaces of the teeth will have no projecting fibers.

The amount of Wax preferred is 1% of the binder employed. The Wax also acts as an additional lubricant as well as insuring a smooth finished surface. Al lubricant, such as soap-stone, or the, like, may replace the graphite in the 'mixture which is applied to the sheet material after being drawn through a bath of an adhesive material. The amount of lubricant is usually 15% of the total Weight of materialin the product but this amount may be varied according to the degree of lubrication required.

Although li have specifically described a method of constructing a spur-gear in accordance with my invention, it is obvious that other machine elements may be conincrease structed in a similar manner without departing from the spirit of my invention. v

,limitations shall be imposed except such as are indicated in the appended claims.

l claim as my inventlon:

1. A self-sustaining gear comprising superimposed layers of duck impregnated With a .hardened phenolic condensation product having a mixture of graphite and Wax uniformlv distributed therein.

2. A self-sustaining gear`comprising superimposed layers of duck impregnated with a hardened phenolic condensation product containing Wax.

lin -test1mony whereof, if have hereunto subscribed my name this 29th day of June, 1918.

\ JOHN' R. MCCLAJIN. 

